You've heard your friends talking about it. You've seen the ads. You know the big names — DraftKings, FanDuel, BetMGM. Maybe you've even downloaded one of those apps. But if someone asked you right now to explain what a spread is, you might hesitate.
You're not alone. Most sports bettors start betting before they understand how it works. This guide changes that.
The Two Basic Ways to Bet
Moneyline bets: You pick who wins. That's it. If you bet the Chiefs moneyline and they win, you win. If they lose, you lose.
The catch: not every team is priced the same. A heavy favorite might be -300, meaning you'd have to bet $300 to win $100. A heavy underdog might be +250, meaning a $100 bet wins $250.
The spread: Instead of just picking the winner, you're betting by how much they win or lose. A team favored by 7 points is -7. If you bet them, they need to win by more than 7 points for you to win your bet. The underdog team is +7 — they can lose by up to 6 points and you still win.
Spreads exist because picking who wins is often obvious. They make the bet even.
What Is -110?
Almost every spread bet you'll see is priced at -110. That means you bet $110 to win $100.
Why not -100 (even odds)? Because the sportsbook takes a cut — this is called the vig (or juice). It's the most important number to understand in sports betting, and we'll cover it in depth in [Article 2].
For now, know this: at -110, you need to win 52.4% of your bets just to break even. Not 50%. 52.4%. That extra 2.4% is the house's margin on every single game you bet.
Totals (Over/Under)
A third common bet type: instead of picking a team, you bet on the total points scored in a game. "Over 47.5" means you need the teams to score 48 combined points or more. "Under 47.5" means 47 or fewer.
Same -110 pricing. Same 52.4% break-even requirement.
Player Props
You can also bet on individual player performance: Will LeBron score over or under 27.5 points tonight? Will Patrick Mahomes throw more or fewer than 2.5 touchdowns?
Props have become one of the most popular bet types because they let you bet on a specific player without caring which team wins. They're also where the market is least efficient — meaning there's often more value here than in straight game lines.
Parlays: The Tempting Trap
A parlay combines multiple bets into one. Get all of them right and you win a multiplied payout. Miss one and you lose everything.
Parlays are the sportsbook's most profitable product. The mathematics are stacked against you — not because the bets are rigged, but because the house takes its margin on each leg separately, compounding.
We dedicate all of [Article 8] to the math behind parlays and when — if ever — they make sense.
What's a Sportsbook?
A sportsbook (FanDuel, DraftKings, BetMGM, Caesars, etc.) is the platform where you place bets. They set the odds, take your money when you lose, and pay you when you win.
Sportsbooks are businesses. Their goal is not to predict the outcome of games — it's to attract balanced action on both sides and collect the vig regardless of who wins. This is a critical distinction we explain in detail in [Article 2].
The Bottom Line for Beginners
Three things to understand before you place your first bet:
- The vig means you start every bet slightly behind. The math does not favor you by default.
- You don't need to predict games correctly 50% of the time to lose money. You need 52.4%. There's a difference.
- There are ways to beat the math — but they require tools and habits most bettors don't have.
That's what the rest of this guide is about.
Next: [How Sportsbooks Make Money (And Why Most Bettors Lose) →]
[Track your first bets free with Oddible — see whether you're winning or losing in real time →]